Additions to Palaeocarpilius rugifer Stoliczka from the Oligocene of Kutch, western India

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1 Bulletin of the Mizunami Fossil Museum, no. 36 (2010), p , 1 pl., 1 fig , Mizunami Fossil Museum Additions to Palaeocarpilius rugifer Stoliczka from the Oligocene of Kutch, western India Francisco J. Vega1, Jugal K. Tiwari2, and Sunil Bajpai3 1 Instituto de Geología, UNAM, Ciudad Universitaria, Coyoacán, México DF, 04510, Mexico, <vegver@unam.mx> 2 Centre for Desert and Ocean, Village Moti Virani, Nakhtrana Taluja, District Kutch (Gujarat), India 3 Department of Earth Sciences, Indian Institute of Technology, Roorkee, India Abstract Specimens of Palaeocarpilius rugifer Stoliczka, from the Oligocene of Kutch, northwest India, are reported and illustrated. The species has not been illustrated since its original publication in The specimens provide information on the range of size for this species, as well as morphologic details to complete the original description. Key words: Crustacea, Carpiliidae, Oligocene, India Introduction poor preservation, we feel that above similarities are enough to merge these specimens with that of Noetling s (1901). Hence, the specimens Crabs of the genus Palaeocarpilius (A. Milne-Edwards, 1862) are a are assigned to Palaeocarpilius rugifer Stoliczka. This statement is relatively common element of Eocene to Miocene assemblages around somewhat confusing, as Noetling (1901) did not mention P. rugifer in the world, but most particularly in Europe (Satsangi and Changkakoti, his work. 1989; Portell, 2004; Beschin et al., 2005; De Angeli et al., 2007; In their list of fossil decapods from Paleogene and Neogene localities Marangon and De Angeli, 2007; De Angeli and Beschin, 2008). Of the of southern Pakistan and western India, Schweitzer et al. (2004, 14 species known for the genus (Schweitzer, 2003; Beschin and De table 1) omitted mention of Palaeocarpilius rugifer, and included P. Angeli, 2006), the type species, P. macrocheilus (Desmarest, 1822) macrocheilus as listed by Sastry and Mathur (1970), but these authors is probably the best known and profusely illustrated of all the species just mentioned P. rugifer instead. of the genus (Beschin et al., 1996; Beschin et al., 2001; De Angeli The specimens here reported include the morphological details and Beschin, 2001; Beschin et al., 2006). Since the original and very described by Stoliczka (1871), and some additional features that are complete description of Palaeocarpilius rugifer Stoliczka, 1871, no commented on the discussion of the species. other occurrences have been reported, except for a mention in Sastry and Mathur (1970), and in a more recent document on Miocene Geological background and location of samples decapods from East India (Ralte et al., 2009), in which one of two specimens identified as P. rugifer is illustrated, with unclear features The Kutch (also spelt Kachchh or Cutch) region of Gujarat, western that related it to the species; if the identification is correct, the species India preserves one of the best developed, fossiliferous marine would then have an Oligocene to Miocene stratigraphic range; however, Tertiary sequences in the Indian subcontinent. The exposures occur in the size of the figured specimen (about 4 4 cm, Ralte et al., 2009, a crescentic belt above the Deccan Traps volcanics of and are about p. 205) is rather small for the mean size of the species, which is rather 900m thick (Biswas, 1992). Since the first detailed work by Wynne large, and therefore the affinity of those specimens is questionable. (1872), the Kutch Tertiary has attracted considerable attention because As the final part of their remarks on P. rugifer, Ralte et al. (2009, p. of the wealth of its fauna, both and macro. Important contributions on 205) stated: Though other characters could not be deciphered due to

2 F. J. Vega et al. 46 designation (= P. macrocheilus var. coronata Bittner, 1886). Palaeocarpilius rugifer Stoliczka, 1871 (Pl. 1, Figs. 1 12) Palaeocarpilius rugifer Stoliczka, 1871, p. 8 10, pl. IV, figs. 1 6, pl. V, figs Description of material: Carapace of large size, subovate transversely, one-third wider than long, widest at lower third; dorsal surface covered by evenly-spaced, fine tubercles, transverse ridges on posterior third of carapace reach posterior tubercle of anterolateral margin, font deflected; anterior margin slightly curved, half the maximum carapace width, orbits circular, inclined 45 respect transversal axis, margin rimmed, outer orbital spine a strong tubercle; anterolateral margin curved, three-fourths the maximum carapace length, with seven strong rounded tubercles, the three anterior tubercles more rounded and less prominent, remainder tubercles become longer, most posterior tubercle being stronger and acute; posterolateral margin smooth, one-third the maximum carapace width, inclined 45 respect transversal axis; posterior margin slightly concave, one-fourth the maximum carapace width. Sternum subtriangular, sternite 3 short, subtriangular, suture between sternites 3 and 4 well defined; sternite 4 subrectangular, elongated, one fifth the maximum carapace length and one-fourth the maximum carapace width, condylus of cheliped coxa articulated on Fig. 1. Location map of fossiliferous outcrop near Ratipar, northeast India, with main lithostratigraphic units. lower fourth of sternite; sternite 5 subsquare, one-fifth the length of sternite 4, condylus of second pereiopod articultated on anterolateral margin; sternite 3 inverted subtapezoidal, one-fifth te length of sternite the geology and paleontology include those by Tewari (1857), Biswas 4, condylus of third pereiopod articulated on anterolateral margin; and Raju (1973), Mohan and Soodan (1970), Raju (1974) and Biswas remainder sternites not seen. Male abdomen triangular, telson plus (1992). The last work provides a useful summary of the litho-, bio- and somites 6 and 5 nearly half the maximum carapace length; telson chronostratigraphy of the Kutch Tertiary succession. triangular, one-seventh the maximum carapace length, one-eight the This small collection of fossil crabs described in this paper was made maximum carapace width; somite 6 subrectangular elongated, nearly by one of us (JKT) from a dry river bed in the Ratipar Reserved Forest as long and wide as telson; somite 5 subtrapezoidal, slightly longer but near Sanghipuram Cement Plant, Abdasa Taluka, District Kutch (Fig. twice the width of telson; somite 4 rectangular, narrow, one-third as 1). The fossils apparently come from blocks eroded away from the long as somite 5; somite 3 similar to somite 4, slightly shorter; somite Oligocene Maniyara Fort Formation which is extensively exposed in the 2 rectangular, similar in size and shape to somite 3; somite 1 not seen. area. This formation has been dated as Oligocene based on foraminifers Female abdomen subovate elongated, telson plus somites 6 to 3 reach including Nummulites and Miogypsina (Biswas, 1992). Preliminary half the maximum carapace length, width is one-third the maximum investigations indicate that the larger benthic foraminifers present carapace width; telson subtriangular, lateral margins broadly rounded, some of the crab-bearing blocks including Nummulites cf. N. fichteli, a one fifth the maximum carapace length, one-sixth the maximum characteristic taxon found in the Maniyara Fort Formation. carapace width; somite 6 rectangular, slightly wider but shorter than The specimens illustrated here are housed in the Paleontology telson; somite 5 rectangular, as wide as somite 6 but half its length; Laboratory, Department of Earth Sciences, Indian Institute of somite 4 similar to somite 5 but slightly shorter; somite 3 very similar Technology, Roorkee, India, under the acronym VPL/SB/KC. in size and shape to somite 4; remainder somites not seen. Chelipeds robust, right cheliped stronger, more massive than left cheliped; Systematic Paleontology coxae subrectangular, strong and acute condylus on proximal and distal articulations; merus subrectangular, robust, one-third maximum Infraorder Brachyura Linnaeus, 1758 carapace width, wider at junction with carpus, with strong condylus; Section Eubrachyura Saint Laurent, 1980 carpus robust, slightly curved, one-third the maximum carapace length, Subsection Heterotremata Guinot, 1977 ventral margin with two tubercles; right propodus robust, subtriangular, Superfamily Carpilioidea Ortmann, 1893 twice its height at distal margin than at proximal margin, its length half Family Carpiliidae Ortmann, 1893 the maximum carapace width, outer and inner surfaces smooth, dorsal Genus Palaeocarpilius A. Milne-Edwards, 1862 margin bears at least three, evenly-spaced strong tubercles, ventral Type species: Cancer macrocheilus Desmarest, 1822, by subsequent margin straight, rimmed at distal portion; fixed finger short, triangular;

3 Palaeocarpilius rugifer from India 47 movable finger curved, subtriangular, slightly longer than fixed finger; left propodus height two-thirds that of right propodus, subtriangular, dorsal margin with at least four, evenly-spaced tubercles, ventral margin rimmed at distal portion; fixed finger short, triangular; movable finger curved, subtriangular, slightly longer than fixed finger; only subovate coxae of remainder pereiopods were preserved. Material and occurrence: Four nearly complete carapaces. Hypotypes VPL/SB/KC 1 to VPL/SB/KC 4. Oligocene Maniyara Fort Formation, Kutch, northwest India. Measurements (in mm): Hypotypes VPL/SB/KC 1, carapace length = 55, width = 75; VPL/SB/KC 2, carapace length = 72, width = 85; VPL/ SB/KC 3, carapace length = 59, width = 78; VPL/SB/KC 4, carapace length = 110, width = 200. Discussion: The specimens from the Oligocene of Kutch are similar in shape and size to those reported by Stoliczka (1871). However, the diagnosis for the species indicate presence of eight tubercles on anterolateral margins, but in counting, Stoliczka included the outer orbital spine as one of the eight counted for the anterolateral margin, and therefore, the number of tubercles should be seven. The female abdomen illustrated by Stoliczka (1871, pl. IV, figs.1, 4) seems to be more slender than that observed in the female specimen of this report, in which the widest segment is abdominal segment 6, while in Stoliczka specimens, segments 4 and 3 are the widest of all. Comparison with female abdomen from other species, such as P. aquitanicus A. Milne Edwards, 1862 (see Beschin and De Angeli, 2006, tavola 2, fig. 1; tavola 3, fig. 3) reveals that the shape of the abdomen is more similar to the one observed in the specimen from Kutch. The male abdomen illustrated by Stoliczka (1871, pl. IV, fig. 5) is very similar to the one observed in our specimens, except for abdominal segment 5, which seems to be longer than on the original drawing of Stoliczka. Satsangi nd Changkakoti (1989) described Palaeocarpilius bispinosus, based on a single, large specimen (length of carapace = 7.8 cm, width = 10.0 cm) from the Middle Eocene of Jaintia Hills, Meghalaya, East India. The original illustration of the holotype is not clear, and as the main feature in which the authors based erection of a new species was presence of only two tubercles on the anterolateral margins, it would be interesting to confirm if the specimen had only two tubercles indeed, or if the remainder tubercles are broken. A large male specimen of similar size is here reported (Figs , hypotype VPL/SB/KC 4, carapace length = 110 mm, width = 200 mm). The morphological features of this large specimen indicate hat it should be classified as P. rugifer, as it has seven large tubercles on anterolateral margins and carapace shape as well as front is similar to the observed in the other specimens of this species. Small differences between P. rugifer and P. aquilinus Collins and Morris, 1973 from the Middle Eocene of Lybia were discussed by Collins and Morris (1973, p. 290), but the species from Lybia is very similar to P. rugifer. The present note was intended to contribute to the knowledge of a species which was originally described more than 100 years ago, with no other specimens reported in this lapse of time. First specimens of Palaeocarpilius rugifer were collected from several localities near our study area, some found transported on streams (Stoliczka, F. 1871; Wynne, 1872) in a region where rocks of the Maniyara Fort Formation of Oligocene age crop out. Foraminifers associated with the decapod specimens described in this note also suggest an Oligocene age for Palaeocarpilius rugifer. Acknowledgments Antonio de Angeli and Torrey Nyborg provided important references. Generous support of H. Karasawa is highly appreciated. Thanks are extended to Ms. Rimjhim Singh for preparing some of the specimens. SB acknowledges funding from the Department of Science and Technology, Government of India (Ramanna Fellowship). References Beschin, C. and A. De Angeli (2006), Il genere Palaeocarpilius A. Milne Edwards, 1862 (Decapoda, Brachyura, Carpiliidae) nel Terziario del Vicentino (Italia Settentrionale). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, 13, Beschin, C., A. Checchi, and S. Ungaro (1996), Crostacei brachiuri dell'oligocene di Castelgomberto (Lessini orientali). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, 6, Beschin, C., A. De Angeli, and A. Checchi (2001), Crostacei decapodi associati a coralli della «Formazione di Castelgomberto» (Oligocene) (Vicenza Italia Settentrionale). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, Beschin, C., A. De Angeli, and A. Checchi (2007), Crostacei dell Eocene Inferiore di cava Rossi di Monte di Malo (Vicenza Italia Settentrionale). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, 14, Beschin, C., A. De Angeli, A. Checchi, and P. Mietto (2006), Crostacei del Priaboniano di Priabona (Vicenza Italia Settentrionale). Lavori, Societá Veneziana di Scienze Naturali, 31, Beschin, C., A. De Angeli, A. Checchi, and G. Zarantonello, (2005), Crostacei Eocenici di Grola Presso Spagnago (Vicenza, Italia Settentrionale). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, 12, Biswas, S. K. (1992), Tertiary Stratigraphy of Kutch. Journal of the Palaeontological Society of India, 37, Biswas, S. K. and D. S. N. Raju (1973), The rock-stratigraphic classification of the Tertiary sediments of Kutch. Bulletin of the Oil & Natural Gas Commission, 10 (1 & 2), Bittner, A. (1886), Neue Brachyuren des Eozäns von Verona. Sitzungsberichte der kaiser Akademie der Wissenschaften in Wien, Mathematisch- Naturwissenschaftliche Klasse, 94, I abteilung, Collins, J. S. H. and S. F. Morris (1973), A new crab from the Middle Eocene of Lybia. Palaeontology, 16(2), De Angeli, A. and C. Beschin (2001), I Crostacei fossili del territorio Vicentino. Natura Vicentina, 5, De Angeli, A. and C. Beschin (2008), Crostacei decapodi dell Oligocene di Soghe e Valmarana (Monti Berici, Vicenza Italia Settentrionale). Studi e Richerche, Associazione Amici del Museo Museo Civico G. Zannato, 15, Desmarest, A. G. (1822), Histoire Naturelle des Crustacés Fossiles. Les Crustacés Proprement Dits. F. G. Levrault, Paris, pp Guinot, D. (1977), Propositions pour une nouvelle classification des Crustacés

4 48 F. J. Vega et al. Décapodes Brachyoures. Compte Rendu Académie des Sciences, Paris, Série D, 285, Linnaeus, C. von (1758), Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. edition 10, volume 1, Laurentii Salvii Homiae (=Stockholm), 824 pp. Marangon, S. and A. De Angeli (2007), New decapod assemblage from the lower Oligocene (Rupelian) of Bacino Ligure Piemontese (NW Italy). Memorie della Società Italiana di Scienze Naturali e del MUseo Civico di Storia Naturale di Milano, 35(2), Milne-Edwards, A. ( ), Monographie des crustacés de la famille cancériens. Annals des Sciences Naturelles, Zoologie, Serie 4, 18(1862), 31 85, pls. 1 10; 20(1863), , pls. 5 12; series 5, 1(1864), 31 88, pls. 1 10; 3(1865), Mohan, M. and K. S. Soodan (1970), Middle Eocene planktonic foraminiferal zonation of Kutch, India. Micropaleontology 16(1), Noetling, F. (1901), The fauna of the Miocene beds of Burma. Palaeontologia Indica, Memoirs of the Geological Survey of India, new series, 1, part 3, Ortmann, A. (1893), Abtheilung: Brachyura (Brachyura genuina Boas), II. Unterabtheilung: Cancroidea, 2. Section: Cancrinea, 1. Gruppe: Cyclometopa. Die DecapodenKrebse des Strassburger Museums, mit besonderer Berücksichtigung der von Herrn Dr. Döderlein bei Japan und bei den Liu-Kiu-Inseln gesammelten und zur Zeit im Strassburger Museum aufbewahrten Formen, VII. Theil. Zoologische Jahrbücher, Abtheilung für Systematik, Geographie, und Biologie der Thiere, 7, Portell, R. W. (2004), Eocene, Oligocene, and Miocene decapod crustaceans. Florida Fossil Invertebrates, 5, 27 pp. Raju, D. S. N. (1974), Observations on the Eocene, Oligocene and Miocene foraminiferal biostratigraphy of Kutch, western India. Publication of the Centre of Advanced Study in Geology, Panjab University, Chandigarh, 10, Ralte, V. Z., J. Lalchawimawii, J. Malsawma, and R. P. Tiwari (2009), Decapod fossils from the Bhuban Formation, Surma Group, Aizawl, Mizoram. Earth Science India, 2 (III), Saint-Laurent, M. de (1980), Sur la classification et la phylogénie des Crustacés Décapodes Brachyoures. II. Heterotremata et Thoracotremata Guinot, Comptes Rendus hebdomadaires des Séances de l Académie des Sciences, Paris, series D, 290, Satsangi, P. P. and U. N. Changkakoti (1989), Fossil decapod Crustacea from Upper Sylhet (Prang) Limestone of Jaintia Hills, Meghalaya. Journal of the Geological Society of India, 34, Schweitzer, C. E. (2003), Utility of proxy characters for classification of fossils: an example from the fossil Xanthoidea (Crustacea: Decapoda: Brachyura). Journal of Paleontology, 77(6), Schweitzer, C. E., R. M. Feldmann, and P. D. Gingerich (2004), New Decapoda (Crustacea) from the Middle and Late Eocene of Pakistan and a revision of Lobonotus A. Milne Edwards Contributions from the Museum of Paleontology, The University of Michigan, 31(4), Stoliczka, F. (1871), Observations of fossil crabs from Tertiary deposits in Sind and Kutch. Memoirs of the Geological Survey of India, Palaeontologica Indica, series 7, XIV, volume 1, part 1, 16 pp. Tewari, B. S. (1957), Geology and stratigraphy of the area between Waghopadar and Cheropadi, Kutch, Western India. Journal of the Palaeontological Society of India, 2, Wynne, A. B. (1872), Memoir on the geology of Kutch, to accompany the map compiled by A. B. Wynne & F. Fedden during the seasons and Memoir of the Geological Survey of India, 9(2), Manuscript accepted on October 16, 2009 Plate 1 Figs Palaeocarpilius rugifer Stoliczka, , Dorsal view of male carapace, hypotype VPL/SB/KC 1; 2, Ventral view of carapace, same specimen; 3, Posterior view of carapace, same specimen; 4, Dorsal view of female carapace, hypotype VPL/SB/KC 2; 5, Ventral view of carapace same specimen; 6, Dorsal view of male carapace, hypotype VPL/SB/KC 3; 7, Ventral view of carapace, same specimen; 8, Detail of female abdomen, hypotype VPL/SB/KC 2; 9, Detail of male abdomen, hypotype VPL/SB/KC 3, A = abdominal segment, St = sternite, Te = telson; 10, Dorsal view of large male carapace, VPL/SB/KC 4; 11, Ventral view of carapace, same specimen; 12, Frontal view of carapace, same specimen. Scale bars = 1 cm.

5 Palaeocarpilius rugifer from India 49 Plate 1